Safety gas-valve.



S. STRAND.

SAFETY GAS VALVE. APPLIOATION FILED 0.0T. 5, 1909.

Patented July 26, 1910.

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SAMUEL STRAND, OF NEW HAVEN, CONNECTICUT.

SAFETY GAS-VALVE.

To all whom it may concern:

Be it known that I, SAMUEL STRAND, a subject of the King of Norway,residing at New Haven, in the county of New Haven and State ofConnecticut, have invented new and useful Improvements in Safety Gas-Valves, of which the following is a specification.

This invention relates to safety gas Valves, and one of the principalobjects of the same is to provide reliable automatic means for cuttingoff the flow of gas to a burner when the light has been extinguished byaccidental means.

Another object of the invention is to provide an automatic safety gasvalve which will cut off thesupply of gas to the burner in case theflame is extinguished by blowing it out, means being provided wherebythe heat of the burner will hold the valve open, and when the flame hasbeen extinguished the cooling of the burner will close the valve andstop the gas supply.

These and other objects may be attained by means of the constructionillustrated in the accompanyii'lg drawing, in which,-

Figure 1 is a longitudinal section taken through a gas burner and safetyvalve made in accordance with my invention. Fig. 2 is a detailtransverse longitudinal section of the valve and its actuatingmechanism. Fig. 3 is a vertical sectional view in lin with the cock.

Referring to the drawing, the numeral 1 designates a casing which, asshown, is of rectangular form in cross section. This casing is providedon its inner side with a lug 2 having a tapering bore therein. Fitted inthe tapering bore is a plug 3 having a finger hold 1 formed thereon,said cock having a set screw 5 for holding the same in place. The lug 2is provided with a slot 6 in one side thereof, and connected to the plug3 is a flat sheet metal valve 7, the lower end of which is adapted torest upon an inclined lug 8 extending across the casing 1. A lever 9pivoted at 10 is provided with a short arm 11, and a spring 12 securedto the casing 1. engages the outer end of the short arm 11 to throw thelonger arm against the valve 7 to hold it closed. Fitted to the casing 1by means of a gas-tight band 13 is a burner tube 14. Fitted in the upperend of the burner tube 14 is a mercury tank having a central tubularportion 15 in the upper end of which is fitted a burner tip 16. Sur-Specification of Letters Patent.

Application filed October 5, 1909.

Patented July 26, 1910. Serial No. 521,058.

rounding the tube 15 is a mercury reservoir 17, and a cylinder 18communicates with the reservoir 17 by means of an opening 19 at the topthereof. A suitable top or cover 20 closes the upper end of the mercurychamber and cylinder.

Mounted to reciprocate in the cylinder 18 is a piston head 21 connectedto a piston rod 22 which extends through the bottom of the cylinder andthrough a guide lug 23 within the burner tube let. A spring 2 1surrounds the piston rod 22, said spring constituting a tension device,the lower end of which is connected with a collar 25 on the piston rodto retract the piston within the cylinder.

Pivotally connected to the lower end of the piston rod is a link 26, andconnected pivotally to the lower end of said link is a bell crank lever28 which is pivoted at 29 to a bracket 30 in the burner tube. Connectedto the bell crank lever 28 is a slide rod 31 guided in a slotted lug 32within the casing 1.. At the end of the slide rod 81 is a roller 33adapted to engage the underside of the valve 7 when the piston 21 isdepressed by the expansion. of the mercury in the cylinder 18.

The operation of my invention may be briefly described as followsz-VVhen it is desired to light the gas the plug 1 is turned to throw thelever 7 to the full line position shown in Fig. 1, after which the gasis ignited at the tip 16. The expansion of the mercury in the reservoirunder the heat of the flame will quickly project the piston 21 againstthe tension of the spring 24:, thus actuating the bell crank lever 28 toproject the slide 31 beneath the valve which is thus retained in an openposition. Should the flame be blown out, or by any accident bediscontinued momentarily, the mercury in the reservoir will become cooland contract, thus causing the piston head to rise under the tension ofthe spring 24, thereby withdrawing the slide 31 from under the valve 7,which latter would drop to its closed or obstructing position assistedby means of the lever 9 and the spring 12.

From the foregoing, it will be obvious that an automatic safety gasvalve made in accordance with my invention would operate efliciently tocut off the gas whenever the latter is extinguished by means of a draftor if blown out or if momentarily discontinued by any cause.

I claim 1. An automatic safety gas valve comprising a casing, a. plugmounted in the casing, a valve connected to the plug, a spring-actuatedlever for holding the valve in closed position, a'burner provided with achamber, said chamber containing a thermally sensitive fluid, a cylindercommunicating with the chamber, a slide rod for engaging the lower sideof the valve, a reciprocating piston in the cylinder having connectionwith the slide rod and operable by the expansion of the thermallysensitive fluid in the cylinder to hold the valve opened, and a springfor moving the piston to close the valve upon the contraction of thethermally sensitive fluid.

2. An automatic safety gas valve comprising a burner provided With achamber,

said chamber containing a thermally sensitive fluid, a gas plug providedWith a valve, a cylinder in the chamber, a reciprocating piston locatedin the cylinder, a springa-ctuated connection between the piston andvalve serving to permit the valve to close when the burner isextinguished, and a thermally sensitive fluid Within the chamber adaptedto flow into the cylinder and depress the piston against the action ofthe spring and hold the valve open when the gas is ignited in theburner.

In testimony whereof I aflix my signature 1n presence of tWo witnesses.

SAMUEL STRAND.

itnesses OLAF LUND, JOHAN Annnnsnn.

